Additional features, settings, or issues not covered by specific Microsoft Teams categories
Hi Vijay7374,
Thank you for the post.
Currently it is not available to create sub task to the existing task at the Planner, we understand your feeling and your requirement. For your demand, we found the same one at the Microsoft Planner user voice. Some issue will may not achievable till many customers demands it. The related team will monitor it and may develop in the future.
Your cooperation is highly appreciated.
Kind Regards,
George